Broker designation and selection in a publish-subscription environment

ABSTRACT

Approaches for designating and/or selecting broker systems in a publication-subscription (pub-sub) messaging environment are provided. In one approach, a subscriber system may be designated as a broker system based on a capability of the subscriber system to function as a broker system for its peers. In another approach, a broker system may be selected from among a plurality of broker systems based upon a cache directory that identifies the content/messages that each broker system may have cached. If a particular broker system has previously cached content that is at least similar to an intended message, that particular broker system may be selected for distributing the intended message to a set of subscriber systems.

TECHNICAL FIELD

Embodiments of the present invention relate to publish-subscription(pub-sub) environments. Specifically, embodiments of the presentinvention relate to approaches for designating and/or selecting brokersystems in a publication-subscription (pub-sub) messaging environment.

BACKGROUND

Publish-subscription (pub-sub) messaging patterns are communicationmodels used in many different industries today. For example, pub-sub isused in banking systems, weather systems, and other systems that requiretechniques to notify multiple entities of common information. Ingeneral, pub-sub is a messaging paradigm where senders (publishers) ofmessages typically are not programmed to send their messages to specificreceivers (subscribers). Rather, published messages can be characterizedinto classes, without knowledge of what (if any) subscribers there maybe. Subscribers express interest in one or more classes and can receivemessages that are of interest, without knowledge of what publishersthere are. This decoupling of publishers and subscribers can allow forgreater scalability and a more dynamic network topology.

One challenge in pub-sub models is determining an efficient route forcommunicating messages to subscriber systems (e.g., from publishersystems). Oftentimes, such communications may occur via a broker systemor the like. As such, selection of an appropriate/capable broker systemmay have a significant impact on the efficient delivery of theunderlying messages.

SUMMARY

In general, embodiments of the present invention relate to approachesfor designating and/or selecting broker systems in apublication-subscription (pub-sub) messaging environment. In oneembodiment, a subscriber system may be designated as a broker system.Specifically, at least one subscriber system having a capability tofunction as a broker system will be identified. The capability of thesubscriber system to provide such function may be determined based uponmetadata stored in at least one computer memory medium. Once a capablesubscriber system has been identified, such subscriber system may thenbe designated as a broker system (e.g., designated as a“subscriber/broker”) so that a set of intended messages may bedistributed by the newly designated broker system to other subscribersystems. In another embodiment, a broker system may be selected fromamong a plurality of broker systems based upon a set of selectioncriteria. Such selection criteria may include a cache directory thatidentifies content/messages that each broker system may have previouslycached. If a particular broker system has previously cached content thatis at least similar to an intended message, and the particular brokersystem has sufficient capacity, that particular broker system may beselected for distributing the intended message to a set of subscribersystems that are subscribed to receive the intended message.

A first aspect of the present invention provides a computer-implementedmethod for designating broker systems in a publish-subscription(pub-sub) messaging environment, comprising: determining a type ofcontent received by a set of subscriber systems in the pub-sub messagingenvironment; identifying at least one subscriber system of the set ofsubscriber systems having a capability to function as a broker systemwith respect to other subscriber systems of the set of subscribersystems, the capability being determined based upon metadata stored inat least one computer memory medium; designating the at least onesubscriber system as the broker system based on the capability; andsending a set of messages having the type of content to the brokersystem for distribution to the other subscriber systems.

A second aspect of the present invention provides at least one systemfor designating broker systems in a publish-subscription (pub-sub)messaging environment, comprising: at least one bus; at least oneprocessor coupled to the at least one bus; and at least one memorymedium coupled to the at least one bus, the at least one memory mediumcomprising instructions to: determine a type of content received by aset of subscriber systems in the pub-sub messaging environment; identifyat least one subscriber system of the set of subscriber systems having acapability to function as a broker system with respect to othersubscriber systems of the set of subscriber systems, the capabilitybeing determined based upon metadata stored in at least one computermemory medium; designate the at least one subscriber system as thebroker system based on the capability; and send a set of messages havingthe type of content to the broker system for distribution to the othersubscriber systems.

A third aspect of the present invention provides at least one computerprogram product for designating broker systems in a publish-subscription(pub-sub) messaging environment, the at least one computer programproduct comprising at least one computer readable storage media, andprogram instructions stored on the at least one computer readablestorage media, to: determine a type of content received by a set ofsubscriber systems in the pub-sub messaging environment; identify atleast one subscriber system of the set of subscriber systems having acapability to function as a broker system with respect to othersubscriber systems of the set of subscriber systems, the capabilitybeing determined based upon metadata stored in at least one computermemory medium; designate the at least one subscriber system as thebroker system based on the capability; and send a set of messages havingthe type of content to the broker system for distribution to the othersubscriber systems.

A fourth aspect of the present invention provides a method for deployinga system for designating broker systems in a publish-subscription(pub-sub) messaging environment, comprising: providing at least onecomputer infrastructure being operable to: determine a type of contentreceived by a set of subscriber systems in the pub-sub messagingenvironment; identify at least one subscriber system of the set ofsubscriber systems having a capability to function as a broker systemwith respect to other subscriber systems of the set of subscribersystems, the capability being determined based upon metadata stored inat least one computer memory medium; designate the at least onesubscriber system as the broker system based on the capability; and senda set of messages having the type of content to the broker system fordistribution to the other subscriber systems.

A fifth aspect of the present invention provides a computer-implementedmethod for selecting a message broker in a publish-subscription(pub-sub) messaging environment, comprising: analyzing a cache directoryassociated with a plurality of broker systems in the pub-subenvironment, the cache directory identifying content stored in a set ofcache memory units by the plurality of brokers; identifying a particularbroker system of the plurality of broker systems for distribution of aset of messages from a publisher system to a set of subscriber systems,the particular broker system being identified based on a similarity ofcontent stored in the set of cache memory units to an intended messageto be distributed to the set of subscriber systems; and sending theintended message to the particular broker system.

A sixth aspect of the present invention provides at least one system forselecting a message broker in a publish-subscription (pub-sub) messagingenvironment, comprising: at least one bus; at least one processorcoupled to the at least one bus; and at least one memory medium coupledto the at least one bus, the at least one memory medium comprisinginstructions to: analyze a cache directory associated with a pluralityof broker systems in the pub-sub environment, the cache directoryidentifying content stored in a set of cache memory units by theplurality of brokers; identify a particular broker system of theplurality of broker systems for distribution of a set of messages from apublisher system to a set of subscriber systems, the particular brokersystem being identified based on a similarity of content stored in theset of cache memory units to an intended message to be distributed tothe set of subscriber systems; and send the intended message to theparticular broker system.

A seventh aspect of the present invention provides at least one systemfor selecting a message broker in a publish-subscription (pub-sub)messaging environment, the at least one computer program productcomprising at least one computer readable storage media, and programinstructions stored on the at least one computer readable storage media,to: analyze a cache directory associated with a plurality of brokersystems in the pub-sub environment, the cache directory identifyingcontent stored in a set of cache memory units by the plurality ofbrokers; determine a particular broker system of the plurality of brokersystems for distribution of a set of messages from a publisher system toa set of subscriber systems, the particular broker system beingidentified based on a similarity of content stored in the set of cachememory units to an intended message to be distributed to the set ofsubscriber systems; and send the intended message to the particularbroker system.

An eighth aspect of the present invention provides a method forselecting a message broker in a publish-subscription (pub-sub) messagingenvironment, comprising: providing at least one computer infrastructurebeing operable to: analyze a cache directory associated with a pluralityof broker systems in the pub-sub environment, the cache directoryidentifying content stored in a set of cache memory units by theplurality of brokers; determine a particular broker system of theplurality of broker systems for distribution of a set of messages from apublisher system to a set of subscriber systems, the particular brokersystem being identified based on a similarity of content stored in theset of cache memory units to an intended message to be distributed tothe set of subscriber systems; and send the intended message to theparticular broker system.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of this invention will be more readilyunderstood from the following detailed description of the variousaspects of the invention taken in conjunction with the accompanyingdrawings in which:

FIG. 1 depicts a computing node according to an embodiment of thepresent invention.

FIG. 2 depicts a pub-sub environment according to an embodiment of thepresent invention.

FIG. 3 depicts a system diagram according to an embodiment of thepresent invention.

FIG. 4 depicts a component flow diagram according to an embodiment ofthe present invention.

FIG. 5 depicts a method flow diagram according to an embodiment of thepresent invention.

FIG. 6 depicts another system diagram according to an embodiment of thepresent invention.

FIG. 7 depicts another component flow diagram according to an embodimentof the present invention.

FIG. 8 depicts another method flow diagram according to an embodiment ofthe present invention.

The drawings are not necessarily to scale. The drawings are merelyschematic representations, not intended to portray specific parametersof the invention. The drawings are intended to depict only typicalembodiments of the invention, and therefore should not be considered aslimiting the scope of the invention. In the drawings, like numberingrepresents like elements.

DETAILED DESCRIPTION

Illustrative embodiments will now be described more fully herein withreference to the accompanying drawings, in which exemplary embodimentsare shown. This disclosure may, however, be embodied in many differentforms and should not be construed as limited to the exemplaryembodiments set forth herein. Rather, these exemplary embodiments areprovided so that this disclosure will be thorough and complete and willfully convey the scope of this disclosure to those skilled in the art.In the description, details of well-known features and techniques may beomitted to avoid unnecessarily obscuring the presented embodiments.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of this disclosure.As used herein, the singular forms “a”, “an”, and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. Furthermore, the use of the terms “a”, “an”, etc., do notdenote a limitation of quantity, but rather denote the presence of atleast one of the referenced items. It will be further understood thatthe terms “comprises” and/or “comprising”, or “includes” and/or“including”, when used in this specification, specify the presence ofstated features, regions, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, regions, integers, steps, operations, elements,components, and/or groups thereof. The term “set” means a quantity of atleast one. Moreover, where reference numbers include the letters “A-N,”it is intended to me a plurality of items.

Embodiments of the present invention allow a subscriber system “peer” tobe designated as a broker system for publishing to other subscribersystems. This may involve the broker system determining what subscribersystems are receiving a certain type of content, and then designating acertain subscriber system as a broker system for other geographicallycollocated subscriber systems to reduce transmission time. Addinganother communication “hop” in this manner would reduce server load/costto operate. This subscriber/broker system (also referred to herein asthe designated broker system) may perform caching at its own level toimprove efficiency. In some embodiments, a subscriber system may opt into become a broker/subscriber system. The primary broker system mayintentionally delay transmission of messages to those subscriber systemsthat have not opted in to become a broker/subscriber system. It may alsobe beneficial to the primary broker system to have manybroker/subscriber “children” systems available to reduce load.Therefore, a delay for those subscriber systems that do not opt-in maymotivate individuals to assist the broker system by opting in.

Embodiments of the present invention further allow a publisher system toselect a particular broker system from a plurality of brokers system forreceiving a message to be distributed to/passed on to applicablesubscriber systems. The selection process may be based on a set offactors/criteria such as broker system availability, geographicproximity of a candidate broker system to applicable/subscribingsubscriber system(s), and what data a broker system may have previouslycached (and thus be a good candidate to receive a new, abbreviatedmessage that may have included similar data). Likewise, a broker systemmay advertise to a cache directory on the contents of the brokersystem's cache. If a publisher system is submitting a new/intendedmessage for publication that is unlike a previous message, the publishersystem may select a broker system with the most free cache space, as tonot remove cache entries from another broker system that anotherpublisher system may still find useful.

Referring now to FIG. 1, a schematic of an example of a computing nodeis shown. Computing node 10 is only one example of a suitable computingnode and is not intended to suggest any limitation as to the scope ofuse or functionality of embodiments of the invention described herein.Regardless, computing node 10 is capable of being implemented and/orperforming any of the functionality set forth hereinabove.

In computing node 10, there is a computer system/server 12, which isoperational with numerous other general purpose or special purposecomputing system environments or configurations. Examples of well-knowncomputing systems, environments, and/or configurations that may besuitable for use with computer system/server 12 include, but are notlimited to, personal computer systems, server computer systems, thinclients, thick clients, hand-held or laptop devices, multiprocessorsystems, microprocessor-based systems, set top boxes, programmableconsumer electronics, network PCs, minicomputer systems, mainframecomputer systems, and distributed computing environments that includeany of the above systems or devices, and the like.

Computer system/server 12 may be described in the general context ofcomputer system-executable instructions, such as program modules, beingexecuted by a computer system. Generally, program modules may includeroutines, programs, objects, components, logic, data structures, and soon that perform particular tasks or implement particular abstract datatypes. Computer system/server 12 may be practiced in distributedcomputing environments where tasks are performed by remote processingdevices that are linked through a communications network. In adistributed computing environment, program modules may be located inboth local and remote computer system storage media including memorystorage devices.

As shown in FIG. 1, computer system/server 12 in computing node 10 isshown in the form of a general-purpose computing device. The componentsof computer system/server 12 may include, but are not limited to, one ormore processors or processing units 16, a system memory 28, and a bus 18that couples various system components including system memory 28 toprocessor 16.

Bus 18 represents one or more of any of several types of bus structures,including a memory bus or memory controller, a peripheral bus, anaccelerated graphics port, and a processor or local bus using any of avariety of bus architectures. By way of example, and not limitation,such architectures include Industry Standard Architecture (ISA) bus,Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, VideoElectronics Standards Association (VESA) local bus, and PeripheralComponent Interconnects (PCI) bus.

Computer system/server 12 typically includes a variety of computersystem readable media. Such media may be any available media that isaccessible by computer system/server 12, and it includes both volatileand non-volatile media, removable and non-removable media.

System memory 28 can include computer system readable media in the formof volatile memory, such as random access memory (RAM) 30 and/or cachememory 32. Computer system/server 12 may further include otherremovable/non-removable, volatile/non-volatile computer system storagemedia. By way of example only, storage system 34 can be provided forreading from and writing to a non-removable, non-volatile magnetic media(not shown and typically called a “hard drive”). Although not shown, amagnetic disk drive for reading from and writing to a removable,non-volatile magnetic disk (e.g., a “floppy disk”), and an optical diskdrive for reading from or writing to a removable, non-volatile opticaldisk such as a CD-ROM, DVD-ROM, or other optical media can be provided.In such instances, each can be connected to bus 18 by one or more datamedia interfaces. As will be further depicted and described below,memory 28 may include at least one program product having a set (e.g.,at least one) of program modules that are configured to carry out thefunctions of embodiments of the invention.

The embodiments of the invention may be implemented as a computerreadable signal medium, which may include a propagated data signal withcomputer readable program code embodied therein (e.g., in baseband or aspart of a carrier wave). Such a propagated signal may take any of avariety of forms including, but not limited to, electro-magnetic,optical, or any suitable combination thereof. A computer readable signalmedium may be any computer readable medium that is not a computerreadable storage medium and that can communicate, propagate, ortransport a program for use by or in connection with an instructionexecution system, apparatus, or device.

Program code embodied on a computer readable medium may be transmittedusing any appropriate medium including, but not limited to, wireless,wireline, optical fiber cable, radio-frequency (RF), etc., or anysuitable combination of the foregoing.

Program/utility 40, having a set (at least one) of program modules 42,may be stored in memory 28 by way of example, and not limitation, aswell as an operating system, one or more application programs, otherprogram modules, and program data. In general, program/utility 40performs the function of the present invention as described herein. Eachof the operating systems, one or more application programs, otherprogram modules, and program data or some combination thereof, mayinclude an implementation of a networking environment. Program modules42 generally carry out the functions and/or methodologies of embodimentsof the invention as described herein. Computer system/server 12 may alsocommunicate with one or more external devices 14 such as a keyboard, apointing device, a display 24, etc.; one or more devices that enable aconsumer to interact with computer system/server 12; and/or any devices(e.g., network card, modem, etc.) that enable computer system/server 12to communicate with one or more other computing devices. Suchcommunication can occur via I/O interfaces 22.

Still yet, computer system/server 12 can communicate with one or morenetworks such as a local area network (LAN), a general wide area network(WAN), and/or a public network (e.g., the Internet) via network adapter20. As depicted, network adapter 20 communicates with the othercomponents of computer system/server 12 via bus 18. It should beunderstood that although not shown, other hardware and/or softwarecomponents could be used in conjunction with computer system/server 12.Examples include, but are not limited to: microcode, device drivers,redundant processing units, external disk drive arrays, RAID systems,tape drives, and data archival storage systems, etc.

Embodiments of the present invention provide an approach for a sharedcache that can be utilized to reduce the volume of data (networktraffic) delivered to individual subscribers in a pub-sub system.Referring now to FIG. 2, a pub-sub environment 70 in accordance with atleast one embodiment of the present invention is shown in greaterdetail. As depicted, environment 70 comprises a publisher system 72(also referred to below as “publisher”) in communication with asubscriber system 74 (also referred to below as “subscriber”) via abroker system 76 (also referred to below as “broker”). Systems 72, 74,and 76 communicate via network links 78A-N, which can represent any typeof network links and/or communication networks now known or laterdeveloped. It is understood that publisher system 72, subscriber system74, and broker system 76 each comprise one or more computer systems12A-C (e.g., which comprise components/elements similar to computersystem 12 of FIG. 1). As such, publisher system 72, subscriber system74, and broker system 76 can each comprise a program/utility 40A-C thatenable corresponding functions thereof. Specifically, publisher system72 comprises publisher program 40A having a set (at least one) ofpublisher program modules 42A, broker system 76 comprises broker program40B having a set of broker program modules 42B, and subscriber system 74comprises a subscriber program 40C having a set of subscriber programmodules 42C. Program modules 42A-C of programs 40A-C typicallyenable/perform the functions that will be described below in conjunctionwith FIGS. 3-8. As further shown, one or more caches 75A-N (e.g., forcontent such as messages) may be provided. In one embodiment, a sharedcache may be utilized hereunder.

As will be further described below, pub-sub system 70 can generallyenable one or more of the following operations: determine a type ofcontent received by a set of subscriber systems in the pub-sub messagingenvironment (e.g. based upon a set of messages previously send to theset of subscriber systems); identify at least one subscriber system ofthe set of subscriber systems having a capability to function as abroker system with respect to other subscriber systems of the set ofsubscriber systems, the capability being determined based upon metadatastored in at least one computer memory medium (e.g., metadata beingreceived via a scan of the set of subscriber systems for the set ofmetadata, a query of the set of subscriber systems, etc.); designate theat least one subscriber system as the broker system based on thecapability; send a set of messages having the type of content to thebroker system for distribution to the other subscriber systems; analyzea cache directory associated with a plurality of broker systems in thepub-sub environment, the cache directory identifying content stored in aset of cache memory units by the plurality of brokers; identify aparticular broker system of the plurality of broker systems fordistribution of a set of messages from a publisher system to a set ofsubscriber systems, the particular broker system being identified basedon a similarity of content stored in the set of cache memory units to anintended message to be distributed to the set of subscriber systems(and/or a geographic proximity to the set of subscriber systems); and/orsend the intended message to the particular broker system.

Regardless, one embodiment of the present invention allows a subscriberpeer to be designated as a broker for publishing to other subscribers.An example of this embodiment is illustrated in FIGS. 3-5. Referringfirst to FIG. 3, a system diagram according to this embodiment is shown.As depicted, FIG. 3 shows a publisher system 72 communicating with abroker system 76. Further, broker system 76 communicates with a set ofsubscriber systems 74A-N. Still yet, any of the systems 72, 74A-N (A-Nbeing used to indicate a plurality of items), and/or 76 of FIG. 3 maycommunicate with and/or utilize one or more cache memory units 75A-C.

In general, the system of FIG. 3 allows broker system 76 to determinewhich subscriber systems 74A-N have historically received a certain typeof content (e.g., based on previous messages or the like stored in acomputer memory medium, databases, cache memory units 75A-C, etc.), andthen designate a particular subscriber system 74A as a broker system forother geographically collocated subscriber systems 74B-N to reducetransmission time (wherein B-N is intended to be indicative of aplurality of other subscriber systems). This may be accomplished inmultiple ways. For instance, broker system 76 may scan for either openlyreadable metadata, or for restricted metadata, about subscriber systems74A-N. Subscriber systems 74A-N may conversely periodically pushmetadata about itself to broker system 76. Still yet, broker system 76may query subscriber systems 74A-N to obtain an active response.Information requested could include geographical specifics, throughputcapacity, information on current queues, and other capabilities that mayguide a determination about the ability of one of subscriber systems74A-N to become a “subscriber/broker” (which subscriber system 74A hasbecome in the example shown in FIG. 3).

It is understood that while the designation of a subscriber system as abroker system may introduce another hop/step in the communicationprocess, such designation should not increase transmission propagationtime. Rather, additional efficiency provided by reduced server load,geographic proximities, and reduced operational costs will typicallyaccount for any transmission time differences. Moreover,subscriber/broker system 74A may perform caching at its own level (e.g.,via cache 75C) to be improve efficiency. In some embodiments, asubscriber system may opt in (or out) to become a broker/subscriber.Primary broker system 76 may intentionally delay the transmission ofmessages to subscriber systems that have not opted in to become abroker/subscriber system.

It may also be beneficial to the primary broker system 76 to havemultiple broker/subscriber “children” available to reduce communicationsloads. As such, a delay for the subscriber systems that do not opt inmay motivate other subscriber systems to assist the broker by opting in.Alternatively, pricing mechanisms may be created to allow subscribersystems to still receive minimal content latency without service as abroker/subscriber. In this case, designation as a broker/subscribersystem 74A may be considered the standard operating procedure.Information recipients may pay a premium price to opt out of the need toperform this dual purpose role, where charges may be incurred by timeperiod (e.g., day, month, or year); by data quantity received (e.g.,kilobyte, gigabyte, terabyte, etc.); or by messages received, etc. Inthis event, the network may accommodate new broker/subscriber systems.However, a premium service may allow subscriber systems to functionsolely as (legacy styled) message subscribers.

Referring now to FIG. 4, a component flow diagram according to anembodiment of the present invention is shown. As depicted, FIG. 4 showscommunications between publisher system 72 having publisher engine 100,broker system 76 having broker engine 102, subscriber/broker system 74Ahaving subscriber/broker engine 104A, and subscriber system 74N havingsubscriber engine 104N. Engines 100, 102, 104A-N generally implementand/or enable the underlying functions of each respective system.Moreover, engines 100, 102, and 104A-N may be implemented as, or work inconjunction with, program 40 of FIG. 1 (and/or programs 40A-C of FIG.2). As further shown, each system may optionally utilize one or morecache memory units 75A-N.

In step M1, publisher system 72 will generate a message that is sent tobroker system 76 in step M2. Upon receiving the message in step M3,broker system 76 will attempt to designate a subscriber system (e.g.,74A-N) as a broker/subscriber system in step M4. In so doing, subscriberdata (e.g., metadata pertaining to capacities, geographic locations,throughput capacity, messages previous cached, etc.) will be provided insteps M5 and M6 (e.g., received in a computer memory medium or the likeof broker system 76). The subscriber data will be analyzed and processedso that a particular subscriber system may be designated as asubscriber/broker system in step M7. This determination may be basedupon the metadata (e.g., which subscriber system is most “capable” tofunction as a broker system). Once a designated broker system 74A hasbeen determined, the message may be sent thereto in step M8. Uponreceiving the message in step M9, designated broker system 74A willdistribute the same to applicable subscriber systems such as subscribersystem 74N in step M10. This message will be received and utilized bysubscriber system 74N in step M11. It is understood that although thedesignation of a subscriber system as a broker system is described asbeing performed by broker system 76 (e.g., engine 102), this need not bethe case. Rather such functionality could be performed by publishersystem 72 (e.g., engine 100)

In sending and receiving messages, any of the systems of FIG. 4 mayutilize cache memory units 75A-N to store content. Such storage may behelpful in the event a future message is generated with similar orcommon content to a previous message. In such a case, an entire newlygenerated message need not be sent. Rather, a system may send the partsof the newly generated message that are not in common with contentpreviously cached. This reduces transmission time, bandwidth, etc.Example(s) of how a caching operation may be implemented hereunder willbe described below.

Referring now to FIG. 5, a method flow diagram according to anembodiment of the present invention is shown. As depicted, in step N1, atype of content received by a set of subscriber systems in the pub-submessaging environment is determined. In step N2, at least one subscribersystem of the set of subscriber systems having a capability to functionas a broker system with respect to other subscriber systems of the setof subscriber systems is determined (the capability being determinedbased upon metadata stored in at least one computer memory medium). Instep N3, the at least one subscriber system is designated as the brokersystem based on the capability. In step N4, a set of messages having thetype of content is sent to the broker system for distribution to theother subscriber systems.

Referring now to FIG. 6, a system diagram according to anotherembodiment of the present invention is shown. In general, the system ofFIG. 6 allows for a broker system to be selected from among a pluralityof broker systems 76A-N for distribution of an intended message or thelike. That is, embodiments of the present invention allow a publishersystem 72 to select a particular broker system (e.g., broker system 76A)from a plurality of broker systems 76A-N for receiving a message to bepassed on to applicable subscriber system(s) 74.

The selection of a particular broker system 76A may be based on a set offactors/criteria such as broker system availability, geographicproximity to subscriber(s), and what data a broker system may havepreviously cached (and thus be a good candidate to receive a new,abbreviated message that would have included the same data). Likewise,broker systems 76A-N may write to a cache directory 78 regarding howfull their cache memory unit(s) 75A-N are. If publisher system 72 issubmitting a new intended message for publication that is unlike aprevious message, publisher system 72 may opt for a broker system withthe most free cache space, as to not remove cache entries from anotherbroker system that another publisher system may wish to utilize.

In general, broker selection may occur through multiple techniques. Inone instance, publisher system 72 may query broker system 76A-N to learnof the applicable criteria, and broker systems 76A-N may respond in anactive fashion. In another instance, broker systems 76A-N mayperiodically write their status and criteria into open registers thatmay be read by any publisher system 72. In yet another instance, brokersystems 76A-N may periodically update its status, conveying theinformation directly back to publisher system 72.

Referring now to FIG. 7, a component flow diagram according to anembodiment of the present invention is shown. As depicted, FIG. 7 showscommunications between publisher system 72 having publisher engine 120,broker system 76A having broker engine 122, and subscriber system 74Nhaving subscriber engine 124. Engines 120, 122, and 124 generallyimplement and/or enable the underlying functions of each respectivesystem. Moreover, engines 120, 122, and 124 may be implemented as, orwork in conjunction with program 40 of FIG. 1 (and/or programs 40A-C forFIG. 2). As further shown, each system may optionally utilize with oneor more cache memory units such as cache memory unit 75A.

In step R1, publisher system 72 will generate a message and then accessa cache directory 78 in step R2. This access is to find an appropriatebroker for publishing the generated message. Based on a set of criteriasuch as what each available broker system has cached (e.g., previousmessages stored in cache memory unit 75A as indicated in cache directory78, publisher system 72 will select a particular broker system such asbroker system 76A in step R3, and then send the message thereto in stepR4. Upon receiving the message in step R5, broker system 76A may performa cache analysis to see if a previous version with similar content waspreviously cached in step R6. As indicated below, this may be used tosend an abbreviated message to reduce bandwidth consumption and thelike. In any event, the intended message will be sent to applicablesubscriber systems 74 in step R7 where it may be received in step R8.

Referring now to FIG. 8, a method flow diagram according to anembodiment of the present invention is shown. In step T1, a cachedirectory associated with a plurality of broker systems in the pub-subenvironment is analyzed, the cache directory identifying content storedin a set of cache memory units by the plurality of brokers. In step T2,a particular broker system (of the plurality of broker systems) isidentified for distribution of a set of messages from a publisher systemto a set of subscriber systems, the particular broker system beingidentified based on at least one of the following: a similarity ofcontent stored in the set of cache memory units to an intended messageto be distributed to the set of subscriber systems, broker availability,or geographic proximity to the set of subscriber systems. In step T3,the intended message is sent to the particular broker system.

Data Caching

It is understood that the teachings recited herein may be performed inconjunction with any data caching operations to facilitate and/or makemore efficient a message publication-subscription implementation (e.g.,carried out by publishers, brokers, and/or subscribers). Shown below areillustrative implementations for caching data hereunder. It isunderstood that these examples are intended to be illustrative only andare non-exhaustive.

Illustrative Implementation I

As a broker system identifies data to be cached, the broker system maycreate a message that contains data that should be in thesubscriber/client's cache, an applicable system/engine may either deleteor substitute the cached data with the appropriate cache key (the systemthat allows for the data to be deleted is described below). For example,assume that the message being sent appears as follows:

AAAAAABBBBBBBCCCCCCDDDDDDEEEEEEE

The broker system indicates that the “B's” of the message will likely beused in future messages and instructs subscribers (both publishers andsubscriber systems) that both should retain the portion in their localcache. In this example, the broker system informs subscriber that theyneed to refer to this portion BBBBBBB as ˜rp1. How to identify repeatedportions will be user specifiable, and the escape sequences to identifyrepeated portions will be user specifiable as well. The subscriber willstore the portion BBBBBBB and analyze incoming messages for the presenceof ˜rp1.

Further assume that at some future point in time, a publisher wants tosend a message that appears as follows:

FFFFFFFFBBBBBBBUUUUUUJJJJJJJJ

Rather than sending this message, it can now send the following:

FFFFFFFF˜rp1 UUUUUUJJJJJJJJ

This allows for the sender to send less traffic on the network. Uponreceipt of this message, the subscriber will then reconstruct themessage based on translation information from its cache and create thefollowing message:

FFFFFFFFBBBBBBBUUUUUUJJJJJJJJ

After expanding ˜rp1 to BBBBBBB.

Illustrative Implementation II

If it was desired, for example, that cached data be inserted at the 12thposition of the message, then a property (or custom header) would beprovided that indicates rp1=12,x,y (where rp1 is the cache key, and 12is the first position to insert the data, x is the next, y is the next,and so on). This method prevents having to escape any un-cached messagedata that matches a cache indicator.

Illustrative Implementation III

Another possible storage key mechanism is the use of Cyclic RedundancyCheck (CRC) or similar technologies. By publishing the repeating datafield, and an indication that this is a repeating (e.g., cacheable)field, the broker system may likewise either send the CRC or allow thesubscriber system to calculate that data field's CRC. Subsequent cacheretrieval instructions can be made by using this CRC as a uniqueidentifier of the cacheable data to be retrieved.

Under embodiments of the present invention, multiple approaches may beincluded in these solutions. Specifically, several techniques may beimplemented to identify cacheable information. The techniques identifiedbelow may be used independently or in conjunction with each other.

Differencing Engine: This approach analyzes messages either within asingle topic, or across multiple topics, capturing the similaritiesbetween messages. The most similar aspects of the messages are goodcandidates for future caching. The similarities captured may bepersisted across restarts such that caching efficiency is notinterrupted. The items cached may change over time as the messageprofiles change. For example, if one type of message is dominant for aperiod of time, then a second disparate message type is dominant, cacheentries related to the first type may be invalidated to make room forthe second type.

Rate-Based Selection: It may be common for some messages and topics tohave a higher rate of publishing than others. This rate may be relatedto the importance or the dynamic nature of the subject for eachparticular topic. Topics with a higher publication rate should beselected for caching before topics with a lower publication rate.Rate-based selection counts the total number of messages per topic, ormessage types within a single topic, and selects the most publishedtopics or message types for message portion caching.

Message Correlation Selection: The system may discern correlationsbetween related topics and therefore cache the potential similaritiesfor the related topics upon detection of the first message. For example,there may be related topics of /scores/[court]/ and /stats/[court] wherecourt is a changing topic related to particular players on a particularcart. Every message published to a /stats/[court] is preceded by amessage published to a /scores/[court]. Both sets of messages mayidentify the player names for that particular court. Therefore, thismethod may discern for every message published to a /scores/[court] anda /stats/[court] that while components of the message change (currentscore, current stats) the player names stay the same. Therefore, for ashort period of time after a message is published to a /scores/[court]the player name component is eligible for caching until thecorresponding /stats/[court] message is sent.

Finally, it is also noted that different methods of signifying dataentities may be used by both senders and recipients of data. Thesemethods include universal hashing, hashing with checksums, rollinghashes, or even cryptographic hash functions, should security dictate.Each of these approaches offers certain advantages and can be used tospeed and ease the implementation of any concepts described in thisdisclosure.

While shown and described herein as broker designation and/or selectionsolution, it is understood that the invention further provides variousalternative embodiments. For example, in one embodiment, the inventionprovides a computer-readable/useable medium that includes computerprogram code to enable a computer infrastructure to provide brokerdesignation and/or selection functionality as discussed herein. To thisextent, the computer-readable/useable medium includes program code thatimplements each of the various processes of the invention. It isunderstood that the terms computer-readable medium or computer-useablemedium comprise one or more of any type of physical embodiment of theprogram code. In particular, the computer-readable/useable medium cancomprise program code embodied on one or more portable storage articlesof manufacture (e.g., a compact disc, a magnetic disk, a tape, etc.), onone or more data storage portions of a computing device, such as memory28 (FIG. 1) and/or storage system 34 (FIG. 1) (e.g., a fixed disk, aread-only memory, a random access memory, a cache memory, etc.).

In another embodiment, the invention provides a method that performs theprocess of the invention on a subscription, advertising, and/or feebasis. That is, a service provider, such as a Solution Integrator, couldoffer to provide broker designation and/or selection functionality. Inthis case, the service provider can create, maintain, support, etc., acomputer infrastructure, such as computer system 12 (FIG. 1) thatperforms the processes of the invention for one or more consumers. Inreturn, the service provider can receive payment from the consumer(s)under a subscription and/or fee agreement and/or the service providercan receive payment from the sale of advertising content to one or morethird parties.

In still another embodiment, the invention provides acomputer-implemented method for providing broker designation and/orselection functionality. In this case, a computer infrastructure, suchas computer system 12 (FIG. 1), can be provided and one or more systemsfor performing the processes of the invention can be obtained (e.g.,created, purchased, used, modified, etc.) and deployed to the computerinfrastructure. To this extent, the deployment of a system can compriseone or more of: (1) installing program code on a computing device, suchas computer system 12 (FIG. 1), from a computer-readable medium; (2)adding one or more computing devices to the computer infrastructure; and(3) incorporating and/or modifying one or more existing systems of thecomputer infrastructure to enable the computer infrastructure to performthe processes of the invention.

As used herein, it is understood that the terms “program code” and“computer program code” are synonymous and mean any expression, in anylanguage, code, or notation, of a set of instructions intended to causea computing device having an information processing capability toperform a particular function either directly or after either or both ofthe following: (a) conversion to another language, code, or notation;and/or (b) reproduction in a different material form. To this extent,program code can be embodied as one or more of: an application/softwareprogram, component software/a library of functions, an operating system,a basic device system/driver for a particular computing device, and thelike.

A data processing system suitable for storing and/or executing programcode can be provided hereunder and can include at least one processorcommunicatively coupled, directly or indirectly, to memory elementsthrough a system bus. The memory elements can include, but are notlimited to, local memory employed during actual execution of the programcode, bulk storage, and cache memories that provide temporary storage ofat least some program code in order to reduce the number of times codemust be retrieved from bulk storage during execution. Input/outputand/or other external devices (including, but not limited to, keyboards,displays, pointing devices, etc.) can be coupled to the system eitherdirectly or through intervening device controllers.

Network adapters also may be coupled to the system to enable the dataprocessing system to become coupled to other data processing systems,remote printers, storage devices, and/or the like, through anycombination of intervening private or public networks. Illustrativenetwork adapters include, but are not limited to, modems, cable modems,and Ethernet cards.

The foregoing description of various aspects of the invention has beenpresented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed and, obviously, many modifications and variations arepossible. Such modifications and variations that may be apparent to aperson skilled in the art are intended to be included within the scopeof the invention as defined by the accompanying claims.

What is claimed is:
 1. A computer-implemented method for designatingbroker systems in a publish-subscription (pub-sub) messagingenvironment, comprising: determining a type of content received by a setof subscriber systems in the pub-sub messaging environment; identifyingat least one subscriber system of the set of subscriber systems having acapability to function as a broker system with respect to othersubscriber systems of the set of subscriber systems, the capabilitybeing determined based upon metadata stored in at least one computermemory medium; designating the at least one subscriber system as thebroker system based on the capability; and sending a set of messageshaving the type of content to the broker system for distribution to theother subscriber systems.
 2. The computer-implemented method of claim 1,the type of content being determined based upon a set of messagespreviously sent to the set of subscriber systems.
 3. Thecomputer-implemented method of claim 1, further comprising receiving theset of metadata.
 4. The computer-implemented method of claim 3, thereceiving comprising scanning the set of subscriber systems for the setof metadata.
 5. The computer-implemented method of claim 3, thereceiving occurring in response to a query of the set of subscribersystems.
 6. The computer-implemented method of claim 1, the set ofsubscriber systems being further identified based on a geographiclocation of each of the set of subscriber systems.
 7. Thecomputer-implemented method of claim 1, the capability being based uponat least one of the following: geographical specifics of the set ofsubscriber systems, throughput capacities of the set of subscribersystems, or information on current messaging queues of the set ofsubscriber systems.
 8. At least one system for designating brokersystems in a publish-subscription (pub-sub) messaging environment,comprising: at least one bus; at least one processor coupled to the atleast one bus; and at least one memory medium coupled to the at leastone bus, the at least one memory medium comprising instructions to:determine a type of content received by a set of subscriber systems inthe pub-sub messaging environment; identify at least one subscribersystem of the set of subscriber systems having a capability to functionas a broker system with respect to other subscriber systems of the setof subscriber systems, the capability being determined based uponmetadata stored in at least one computer memory medium; designate the atleast one subscriber system as the broker system based on thecapability; and send a set of messages having the type of content to thebroker system for distribution to the other subscriber systems.
 9. Theat least one system of claim 8, the type of content being determinedbased upon a set of messages previously sent to the set of subscribersystems.
 10. The at least one system of claim 8, the at least one memorymedium further comprising instructions to receive the set of metadata.11. The at least one system of claim 10, the at least one memory mediumfurther comprising instructions to scan the set of subscriber systemsfor the set of metadata.
 12. The at least one system of claim 10, themetadata being received occurring in response to a query of the set ofsubscriber systems.
 13. The at least one system of claim 8, the set ofsubscriber systems being further identified based on a geographiclocation of each of the set of subscriber systems.
 14. The at least onesystem of claim 8, the capability being based upon at least one of thefollowing: geographical specifics of the set of subscriber systems,throughput capacities of the set of subscriber systems, or informationon current messaging queues of the set of subscriber systems.
 15. Atleast one computer program product for designating broker systems in apublish-subscription (pub-sub) messaging environment, the at least onecomputer program product comprising at least one computer readablestorage media, and program instructions stored on the at least onecomputer readable storage media, to: determine a type of contentreceived by a set of subscriber systems in the pub-sub messagingenvironment; identify at least one subscriber system of the set ofsubscriber systems having a capability to function as a broker systemwith respect to other subscriber systems of the set of subscribersystems, the capability being determined based upon metadata stored inat least one computer memory medium; designate the at least onesubscriber system as the broker system based on the capability; and senda set of messages having the type of content to the broker system fordistribution to the other subscriber systems.
 16. The at least onecomputer program product of claim 15, the type of content beingdetermined based upon a set of messages previously sent to the set ofsubscriber systems.
 17. The at least one computer program product ofclaim 15, the at least one memory medium further comprising instructionsto receive the set of metadata.
 18. The at least one computer programproduct of claim 17, the at least one memory medium further comprisinginstructions to scan the set of subscriber systems for the set ofmetadata.
 19. The at least one computer program product of claim 17, themetadata being received occurring in response to a query of the set ofsubscriber systems.
 20. The at least one computer program product ofclaim 15, the set of subscriber systems being further identified basedon a geographic location of each of the set of subscriber systems. 21.The at least one computer program product of claim 15, the capabilitybeing based upon at least one of the following: geographical specificsof the set of subscriber systems, throughput capacities of the set ofsubscriber systems, or information on current messaging queues of theset of subscriber systems.
 22. A method for deploying a system fordesignating broker systems in a publish-subscription (pub-sub) messagingenvironment, comprising: providing at least one computer infrastructurebeing operable to: determine a type of content received by a set ofsubscriber systems in the pub-sub messaging environment; identify atleast one subscriber system of the set of subscriber systems having acapability to function as a broker system with respect to othersubscriber systems of the set of subscriber systems, the capabilitybeing determined based upon metadata stored in at least one computermemory medium; designate the at least one subscriber system as thebroker system based on the capability; and send a set of messages havingthe type of content to the broker system for distribution to the othersubscriber systems.
 23. A computer-implemented method for selecting amessage broker in a publish-subscription (pub-sub) messagingenvironment, comprising: analyzing a cache directory associated with aplurality of broker systems in the pub-sub environment, the cachedirectory identifying content stored in a set of cache memory units bythe plurality of brokers; identifying a particular broker system of theplurality of broker systems for distribution of a set of messages from apublisher system to a set of subscriber systems, the particular brokersystem being identified based on a similarity of content stored in theset of cache memory units to an intended message to be distributed tothe set of subscriber systems; sending the intended message to theparticular broker system.
 24. The computer-implemented method of claim23, the particular broker system being further identified based on atleast one of the following: broker availability, or geographic proximityto the set of subscriber systems.
 25. At least one system for selectinga message broker in a publish-subscription (pub-sub) messagingenvironment, comprising: at least one bus; at least one processorcoupled to the at least one bus; and at least one memory medium coupledto the at least one bus, the at least one memory medium comprisinginstructions to: analyze a cache directory associated with a pluralityof broker systems in the pub-sub environment, the cache directoryidentifying content stored in a set of cache memory units by theplurality of brokers; identify a particular broker system of theplurality of broker systems for distribution of a set of messages from apublisher system to a set of subscriber systems, the particular brokersystem being identified based on a similarity of content stored in theset of cache memory units to an intended message to be distributed tothe set of subscriber systems; send the intended message to theparticular broker system.
 26. The at least one system of claim 25, theparticular broker system being further identified based on at least oneof the following: broker availability, or geographic proximity to theset of subscriber systems.